/Engine/Plugins/Media/PixelStreaming/Source/PixelStreamingInput/Public/IPixelStreamingInputHandler.h
Register a function to be called whenever the specified message type is received.
void RegisterMessageHandler ( const [FString](API\Runtime\Core\Containers\FString) & MessageType, const [TFunction](API\Runtime\Core\GenericPlatform\TFunction)< void([FMemoryReader](API\Runtime\Core\Serialization\FMemoryReader))> & Handler )